Not sure if you are referring to the timer in the real exam or in the exam simulator. I do not know about the simulator, but I just took the real exam yesterday and was able to hide the timer by just clicking on it. I discovered this by accident and would not really recommend it, but it is possible to do if it helps you. I say I wouldn't recommend it though because I was completing simulator exams during my preparation with 20-40 minutes to spare. However, in the real exam yesterday, I ended up finishing the last question with about 30 seconds to spare. This was just my personal experience though. It is possible to hide the timer if that fits your style and needs.